Quickstart

This quickstart shows you how to call the Gas API using JavaScript. You can also use a tool such as curl or Postman to call the REST APIs.

tip

View the API reference content to view the curl command for each API.

Prerequisites

• A valid Web3 API key and optional API key secret.
• Node.js and npm installed.

Initialize a new project directory

mkdir new_project
cd new_project
npm init -y

Install required packages

Install the axios package:

npm install axios

Install the dotenv package:

npm install dotenv

Create your .env file

Create a .env file at the project root and add the following data:

warning

Do not commit the .env file to your repository if it contains sensitive data. You can create a .gitignore file to prevent accidentally committing the file.

.env

INFURA_API_KEY=<API-KEY>
INFURA_API_KEY_SECRET=<API-KEY-SECRET>

Replace the Infura project credential placeholders with your own.

note

The INFURA_API_KEY_SECRET is optional and only necessary if you are using an API key secret to authenticate requests.

Create your script

The Gas API supports multiple request formats, and you can call the methods with or without specifying an API key secret.

Create a file (in this example index.js):

touch index.js

Copy the following code into your script:

note

If using a network other than Ethereum Mainnet, update the chainId value (1) in the code to an alternate supported network.

Use an API key only

index.js

const axios = require("axios");
require("dotenv").config();

// The chain ID of the supported network
const chainId = 1;

(async () => {
  try {
    const { data } = await axios.get(
      `https://gas.api.infura.io/v3/${process.env.INFURA_API_KEY}/networks/${chainId}/suggestedGasFees`
    );
    console.log("Suggested gas fees:", data);
  } catch (error) {
    console.log("Server responded with:", error);
  }
})();

Use an API key and API key secret

index.js

const axios = require("axios");
require("dotenv").config();

const Auth = Buffer.from(
  process.env.INFURA_API_KEY + ":" + process.env.INFURA_API_KEY_SECRET,
).toString("base64");

// The chain ID of the supported network
const chainId = 1;

(async () => {
  try {
    const { data } = await axios.get(
      `https://gas.api.infura.io/networks/${chainId}/suggestedGasFees`,
      {
        headers: {
          Authorization: `Basic ${Auth}`,
        },
      },
    );
    console.log("Suggested gas fees:", data);
  } catch (error) {
    console.log("Server responded with:", error);
  }
})();

Run the script

node index.js

The result should look similar to:

Suggested gas fees: {
  low: {
    suggestedMaxPriorityFeePerGas: "0.05",
    suggestedMaxFeePerGas: "24.086058416",
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 30000
  },
  medium: {
    suggestedMaxPriorityFeePerGas: "0.1",
    suggestedMaxFeePerGas: "32.548678862",
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 45000
  },
  high: {
    suggestedMaxPriorityFeePerGas: "0.3",
    suggestedMaxFeePerGas: "41.161299308",
    minWaitTimeEstimate: 15000,
    maxWaitTimeEstimate: 60000
  },
  estimatedBaseFee: "24.036058416",
  networkCongestion: 0.7143,
  latestPriorityFeeRange: [ "0.1", "20" ],
  historicalPriorityFeeRange: [ "0.007150439", "113" ],
  historicalBaseFeeRange: [ "19.531410688", "36.299069766" ],
  priorityFeeTrend: "down",
  baseFeeTrend: "down"
}